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-rw-r--r--drivers/char/hw_random/meson-rng.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/drivers/char/hw_random/meson-rng.c b/drivers/char/hw_random/meson-rng.c
new file mode 100644
index 0000000000..a4eb8e35f1
--- /dev/null
+++ b/drivers/char/hw_random/meson-rng.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+/*
+ * Copyright (c) 2016 BayLibre, SAS.
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ * Copyright (C) 2014 Amlogic, Inc.
+ */
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/hw_random.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/of.h>
+#include <linux/clk.h>
+
+#define RNG_DATA 0x00
+
+struct meson_rng_data {
+ void __iomem *base;
+ struct hwrng rng;
+};
+
+static int meson_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
+{
+ struct meson_rng_data *data =
+ container_of(rng, struct meson_rng_data, rng);
+
+ *(u32 *)buf = readl_relaxed(data->base + RNG_DATA);
+
+ return sizeof(u32);
+}
+
+static int meson_rng_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct meson_rng_data *data;
+ struct clk *core_clk;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(data->base))
+ return PTR_ERR(data->base);
+
+ core_clk = devm_clk_get_optional_enabled(dev, "core");
+ if (IS_ERR(core_clk))
+ return dev_err_probe(dev, PTR_ERR(core_clk),
+ "Failed to get core clock\n");
+
+ data->rng.name = pdev->name;
+ data->rng.read = meson_rng_read;
+
+ return devm_hwrng_register(dev, &data->rng);
+}
+
+static const struct of_device_id meson_rng_of_match[] = {
+ { .compatible = "amlogic,meson-rng", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, meson_rng_of_match);
+
+static struct platform_driver meson_rng_driver = {
+ .probe = meson_rng_probe,
+ .driver = {
+ .name = "meson-rng",
+ .of_match_table = meson_rng_of_match,
+ },
+};
+
+module_platform_driver(meson_rng_driver);
+
+MODULE_DESCRIPTION("Meson H/W Random Number Generator driver");
+MODULE_AUTHOR("Lawrence Mok <lawrence.mok@amlogic.com>");
+MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
+MODULE_LICENSE("Dual BSD/GPL");